Fire extinguisher warning system



8, 1964 v. B. WEBB 3,145,375

FIRE EXTINGUISHER WARNING SYSTEM 3 Sheets-Sheet 1 IN VEN TOR.

Vern B. Webb BY WHITEHEAD, VOGL a LOWE PER Fig. 3 Fig. 5 M/ 6% ATTORNEYS Aug. 18, 1964 V. B. WEBB FIRE EXTINGUISHER WARNING SYSTEM Filed May 29. 1961 7\- 3 Sheets-Sheet 2 VI 857 gen 1 lf-:

Fig. 9

INVENTOR.

Vern B. Webb BY WHITEHEAD, VOGL a LOWE ATTORNEYS Aug. 18, 1964 v. B. WEBB 3,145,375

FIRE EXTINGUISHER WARNING SYSTEM INVENTOR.

Vern B. Webb BY WHITEHEAD, VOGL a LOWE PERJY A A- ATTORNEYS United States Patent Q 3,145,375 Fil -1E EXTMGUESHER WARNKNG SYSTEM Vern B. Webb, Midvale, Utah (4343 Detroiter Circle, Murray, Utah) Filed May 29, 196i, Ser. No. 113,441 9 tliairns. ill. Mil-"2843) This invention relates to control systems for use with emergency equipment such as fire extinguishers and more particularly to an improved control system for use with emergency equipment which will help a user to locate the equipment and which will warn maintenance personnel that the equipment is being used or has been used. The invention relates specifically to a control system for manually operated fire extinguishers. As such, the invention will be hereinafter referred to and described as a fire extinguisher warning system, although it is to be understood that the invention may be used for other types of equipment.

The common manner of installing manually operated fire extinguishers is to spot the extinguishers at strategic locations throughout a building or in an industrial plant for emergency use whenever the occasion is required. Such a system of installing fire extinguishers is quite common, is generally satisfactory and an installation at one location will differ little from that at another location. However, means for effectively directing a workers attention to the extinguisher and/ or for warning the proper maintenance personnel that the extinguisher is being used or has been used, are lacking at most installations, and, at best, are awkward. Sometimes, a dull red light is located near the extinguisher to help a user to locate it in an emergency. Also, it has been proposed to trip an alarm when the fire extinguisher is removed from its hanger or shelf. Beyond these simple expedients which are not in general use, there have been no significant improvements in warning systems for fire extinguishers.

There is nevertheless a real and definite need for an improved and a comprehensive warning system for fire extinguishers in a number of modern industrial establishments, such as defense plants, large buildings and factories where the tenants or personnel are so numerous that there is a good chance that the user of a fire extinguisher may never report, or his report may never reach, the proper maintenance personnel. This can, and often does, result in an empty fire extinguisher being returned to its hanger and in place for use in the event of a possible subsequent fire.

It was with such need in mind that the present invention was conceived and developed and the invention comprises, in essence, a multi-purpose warning system which assists an individual in locating the extinguisher, which initiates a warning signal when the extinguisher is removed from its hanger and which continues to emit this warning signal when the extinguisher is returned to its hanger. This continuous warning signal may be turned off only with a key held by the maintenance personnel who have the responsibility of recharging the extinguisher after it has been used. The value of such a system can be fully appreciated by a simple example which occurs repeatedly. An ofiice worker accidentally starts a superficial fire, usually in his wastebasket. He uses an extinguisher provided by the building to put it out but then because of personal reasons, he returns the empty extinguisher to its hanger without reporting the incident.

It follows that the principal object of the invention is to provide a novel and improved fire extinguisher warning system which assists an individual in locating the extinguisher, issues a warning signal whenever the extinguisher is removed as for use and continues to issue the warning signal after the extinguisher is replaced.

Another object of the invention is to provide a novel and improved fire extinguisher warning system which includes a flashing visual means to facilitate the location of an extinguisher in the dark, in unlit halls and rooms and also, even at other locations which are adequately lighted.

Another object of the invention is to provide a novel and improved fire extinguisher warning system which will visually signal the removal of the extinguisher from its hanger with one signal being at the'hanger location and, if desired, another signal being at a remote location, such as at the central control room of an industrial plant.

Another object of the invention is to provide a novel and improved fire extinguisher warning system which will provide a continuous visual warning signal upon the removal of a fire extinguisher, which may also indicate the return of the extinguisher to its hanger but which will continue to issue the warning signal to indicate that the extinguisher has been used.

Another object of the invention is to provide a novel and improved fire extinguisher warning system having a visual flashing signal to facilitate locating the extinguisher and a second visual signal to warn of its removal and use, which may be supplemented by audio warning means as at a location away from the extinguisher.

Another object of the invention is to provide a novel and improved fire extinguisher warning system which is especially adapted to visually and/or audibly signal the use of an extinguisher at a remote station, and which may be installed in large buildings, industrial or warehouse plants having many individual fire extinguisher locations and a central control room where it is desirable to know of any removal and use of a fire extinguisher at any location throughout the building or plant.

Yet further objects of the invention are to provide a novel and improved fire extinguisher Warning system, which is a simple, neat, easily installed, low-cost construction and which can operate in a reliable, economical and maintenance free manner for a long period of time.

With the foregoing and other objects in view, all of which more fully hereinafter appear, my invention comprises certain novel and improved constructions, combinations and arrangements of parts, elements and circuits as hereinafter described, defined in the appended claims and illustrated in the accompanying drawing in which:

FIGURE 1 is a perspective, somewhat diagrammatic, view of a portion of a wall having a fire extinguisher mounted thereon, upon a hook, with one embodiment of my improved warning system being also mounted upon and in the wall in operative association with the ex tinguisher and with broken lines indicating wiring circuits and other elements hidden from view.

FIGURE 2 is a fragmentary sectional portion of the wall, a sectional view of the supporting hook, a portion of an extinguisher mounted thereon, and of other elements associated therewith, as taken substantially from the indicated line 22 at FIG. 1, but on an enlarged scale.

FIGURE 3 is a fragmentary sectional portion of the wall and an elevational view of the improved signalling box and other elements associated therewith, all as taken substantially from the indicated line 33 at FIG. 1, but on an enlarged scale and with portions and components being broken away to show constructions otherwise hidden from view.

FIGURE 4 is an isometric view of the signalling box per se, as taken substantially from the indicated arrow 4 at FIG. 1, but on an enlarged scale.

FIGURE 5 is a sectional plan view of portions of the indicator box as taken substantially from the indicated line 55 at FIG. 4, and illustrating further, the manner of using a reset key in the apparatus.

FIGURE 6 is a perspective, somewhat diagrammatic,

are.

view of a portion of a wall having a fire extinguisher, mounted thereon, similar to FIG. 1, and of a portion of another wall remote from the first, with another embodiment of the improved warning system, as modified to provide signals of useof the fire extinguisher at the remote location.

FIGURE 7 is an isometric view of a signalling box adapted for visual and audible use and especially at a remote location, as taken substantially from the indicated arrow 7 at FIG. 6, but on an enlarged scale.

FIGURE 8 is an elevational, diagrammatic view, illustrating a Wall portion having a fire extinguisher mounted thereon and a second wall portion remote from the first, whereon a further modification of the warning system is installed.

FIGURE 9 is a circuit diagram of a circuit adapted to operate the embodiment illustrated at FlGS. 1 through in accordance with the principles of the invention and with broken lines indicating one means of extending the circuits to a remote station according to the disclosure at FIG. 8.

FTGURE 10 is a circuit diagram adapted to operate the embodiment illustrated at FIGS. 6 and 7 in accordance with the principles of the invention.

Referring more particularly to the drawing, in common practice a fire extinguisher 11 is commonly mounted upon a wall 12, upon a hook 13 at any suitable location as in a hall of a building, or the like. The fire extinguisher is formed as a generally cylindrical unit having a mounting handle 14, a gripping head 15 and a discharge hose 16. In the ordinary soda-acid type of extinguisher it is essential that it be held in a vertical position and it is ordinarily kept with the handle 14 being placed in the Wall hook 13 as illustrated. However, there are other types of extinguishers and there are several arrangements for mounting the extinguishers. Also, the construction of the mounting hook may vary considerably or be completely eliminated, as when the extinguisher is set upon a shelf. It is possible, however, to associate an electrical switch with the fireextinguisher to operate when the extinguisher is properly mounted or set in its stored position as, for example, in the manner illustrated at FIG. 1.

i The electrical switch 20 is essentially a conventional three-wire-two-way type having a rigid body portion 21 which in the construction illustrated may be secured to the wall 12 as by mounting screws 22 at a suitable position below the wall hook 13. The switch includes an actuating lever 23 which extends into a suitable slot in the crotch of the hook 13 at a position where it will be intercepted by the handle 14. whenever the fire extinguisher is mounted therein. The circuits in this switch will include a central lead wire 24 and side lead wires 25 and 26 and the switch will operate by contacting the central lead wire 24 with a side lead wire 25 whenever the fire extinguisher is in the hook 13 or a side lead wire 26 whenever the fire extinguisher is removed from the hook. The leadwires extend to components hereinafter described.

In the embodiment illustrated at FIGS. 1 to 5, the warning system is but a single unit which is preferably located at or adjacent to the fire extinguisher itself. This unit operates signal lights according to a selected code of operation and that code, which was found to be the most effective for helping a user of the extinguisher and to warn maintenance personnel that the fire extinguisher had been removed includes a pair of lights. The first is a flashing amber light 30 which operates continuously to indicate the location of the fire extinguisher and to indicate that it is in its proper place. The flashing amber light is especially desirable in hallways and at locations where it is apt to be dark whenever the extinguisher is needed. Such a light is also especially desirable where theextinguisher is set in a cabinet or recess Where it cannot be easily seen. The second is a red light 31 which is turned on whenever the fire extinguisher is removed from its book. At the same time, the flashing amber light is turned off. This change of lighting is easily noticeable, even though on account of darkness or positioning, the fire extinguisher itself cannot be easily seen. A further phase of operation commences Whenever the extinguisher is returned to the hook, for then the amber light commences to flash again but at the same time, the red light continues to glow. This informs maintenance personnel that the extinguisher has been used and returned and that recharging is probably necessary.

The amber light 3t and red light 31 are housed in a small box-like case 3?; which is mounted upon the wall 12 adjacent to the fire extinguisher. it is mounted over a common electrical outlet box 33 which is recessed in the wall in a conventional manner. A conventional plug-type receptacle body 3d having sockets 35 for a pair of ordinary wall plugs is mounted in this electrical outlet box in a conventional way as by mounting screws 36 and though conventional in form, the body 34 is modified by adapting tl e plug-sockets for individual circuits as hereinafter described.

To mount the housing box 32 over this receptacle, the box is formed with a rear wall 37 of insulated material and two pair of plug-prongs 33 are adapted to outstand from this wall and to fit to the receptacle sockets 35. w

A central mounting screw 36 extends through the rear wall and into the receptacle lid to hold the assembly in place. The outlet box 33 may be covered by an ordinary plate 39 which lies between the housing box 32 and the outlet box 33, all as clearly illustrated at E6. 3.

The housing box is fully enclosed as by the rear wall 37, a pair of side walls 40, a top 41, a bottom 42 and a front wall 43. Suitable openings extend through the walls for the passage of circuit wires, and orifices dd are located in the front wall 43 wherein the lights 39 and 31 are mounted. A tab 45 indicating a serial number is also located on this first face, and a matching tab 45' is located on the fire extinguisher ll for purposes of identification.

An accessory date-indi ating box to, substantially smaller than box 32, is suitably affixed to the upper portion of the housing box 32 as at one thereof. This datc-indicating box is formed as an enclosed unit having a front face 47 which is preferably held flush with the front wall of the housing box 321. A central slotted opening 4-8 is located in the face 47 to expose a group of rotatable numbered dials 4% which are carried within this box. The dials are arranged to indicate month, day and year in any suitable manner and they may be rotated to establish any particular date. For example, they may be used to indicate the last date the extinguisher was checked or replaced. The dials as may be set in any suitable manner such as by using a small-diameter pencillilte rod which may be simply pushed in the slot 48 to rotate them. i

A loch-box 5d also substantially smaller than the box 32 is mounted alongside the housing box 32 preferably below the date indicating box, as illustrated at FIG. 4. This box 50 is fully enclosed with its front face 51 being flush with the front face 43 of the housing box and including a key slot 52. A normally closed spring type switch 53 is mounted within this look box with the cir cuits 54- thereof extending into the housing box as through a grommet-like insulator 55, between the adjoining walls of the boxes. in operation, a suitable key 56 is passed through the slot to deflect the spring switch to open the circuit of the switch.

To complete this assembly a suitable power circuit 57, which will ordinarily be a 119 volt A.C. circuit, is brought from a convenient source to an outlet box 58 which is mounted in the wall in a conventional manner. A conventional type of transformer 5%, shown in broken lines at FIG. 1, is mounted within this box to reduce the voltage of the power circuit 57. The secondary output ciranaaavs cuit leads 60 extend from the box 53 in a convenient manner behind the surface of the wall 12 and to the outlet box 33 as shown in broken lines at FIG. 1. Also, the leads 24, 25 and 26 of the switch 2% extend from the switch behind the wall surface and to the box 33. The circuit wires 66 and the switch leads enter the box as through connectors 61.

The actual electrical components making up the operative circuit in addition to those heretofore described are housed within the box 32 but are not shown at FIGS. 1-5. However, they are exemplified in the circuit diagram at FIG. 9. The voltage of the power circuit 57 is reduced by the transformer 59, and the reduced voltage circuit leads 6%) extend to the apparatus heretofore described. One lead 6th: is directly connected to and becomes the central lead wire 24 of the two-way switch 20. The other lead 6% extends to a bifurcation point 62. The circuit is thus divided into two operative loops with one loop extending from the switch 26 to the bifurcation point 62 for operation of the amber light 33, and the other loop extending from the switch 2% to the bifurcation point 62 for operation of the red light 31.

The two-way switch is illustrated as making contact with the side lead wire which extends directly to the amber light 3%; and the switch is in this position whenever the fire extinguisher 11 is mounted on the wall hook 13 as heretofore described. A branch lead 63 extends from the bifurcation point 62 to the amber light to complete the operative loop to the light 36.

However, it is desired that this amber light operate by periodic flashing and the branch lead 63 is modified to restrict the current flow to an intermittent action, appropriate to flash the amber light 30. A rectifier 64 in the lead 63 and a capacitor 65 in a lead 66 across the leads 63 and 24 changes the electric flow in the operative loop of the light to direct current. A gating transistor 67 controls the current flow through the lead 63. The lead 63 is connected with the collector and emitter of this transistor and the base thereof is connected with a gating. lead 68 which extends from the base of the transistor 67' to the emitter of a starting transistor 69, from the collector thereof and to the side lead 25 and in combination with the portion of the branch lead 63 connected with the emitter of transistor 67 effectively shunt the light 34). This gating lead 68 also includes a suitable resistor 76 to control the charge on the base of the gating transistor 67 responsive to the operation of the starting transistor 69.

The base of the starting transistor 69 is connected to a lead 71 which connects with a starting lead 72 that extends as a loop from the lead 63 at each side of the gating transistor 67 to shunt the transistor 67. This starting lead 72 includes biasing resistors 73 and 73' at each side of the bias lead 71 and a capacitor 74 adjacent to the point of connection with the lead 63 in that portion between the transistor 67 and the light 3%).

In operation, whenever the circuit is energized as by closing the switch 2%, the gating transistor essentially cuts off current flow through the lead 63, but a small current flows through the starting lead 72 to charge the capacitor 74. This causes a voltage drop which acts upon the base of the starting transistor 69, which, in turn, permits a flow of current through the gating lead 68 to charge the base of the gating transistor 67. This action, in turn, permits a surge of current through the lead 63 sufficient to light the light 30. The current surge reaches a peak causing the capacitor 74 to discharge, and to remove the charges from the bases of the transistors 67 and 69. This effectively cuts off the flow through the lead 63 to cut out the light 30.

This system is then at its former state and the action is repeated, with the frequency of the flashing of the light being controlled essentially by the values of the capacitor 74 and the resistors 73 and 73'. A desirable flashing frequency is approximately 120 times per minute.

Whenever the switch 20 is shifted as by removing the 6 fire extinguisher, it makes contact with the side lead wire 26 which extends directly to the red light 31 and the redlight-operative loop is closed. This circuit loop consists of the lead wire 26 at one side of the light and a branch lead 75 which extends from the bifurcation point 62 to the other side of the red light.

Once closed, it is desired that this circuit remain closed and the red light continue to burn even when the switch 2% is disconnected from the contact with the lead 26. This is accomplished by a relay 76. The magnet of this relay is in a lead 77 which shunts the light 31, one end of the lead 77 connecting in lead 26 and the other end of the lead '77 connecting in the branch lead 75. The normally open relay switch, 78 is in a' lead 79 which shunts the switch 2%, one end of the lead 79 being connected in the central lead 24 at one side of the switch 20 and the other end of the lead 79 being connected with the side lead 26. In operation, whenever the circuit formed by leads 26 and 75 is closed by switch 2t? to light the red light 31, the relay magnet 76 is energized to close switch 78. The switch 78 then holds the circuit closed and the red light continues to burn even after the switch 21) is again shifted from contact with lead 26.

Ultimate release of the circuit is obtained by the manually-operated spring switch 53, heretofore described. This switch is located in the circuit 79 and it may be opened, as by key 56 to open all of the circuits, turn off the red light and return the apparatus to its normal position. This will tien indicate that a properly charged fire extinguisher is mounted on the hanger 13 and the amber light will be flashing to indicate the location of the extinguisher.

The modified units illustrated at FIGS. 6, 7 and 8 are adapted to signal the use of a fire extinguisher at a remote station, as in the control room of a building.

The arrangement illustrated at FIG. 8, is, for all practical purposes, the same as that heretofore described. The extinguisher ill is mounted upon a wall section 12, on a hangar 13. The signal housing box 32 includes the flashing amber light 30 and red light 31. Also, it includes the date indicating box 46, the lock box 50 and the identification tag 46. It is operated by a voltage-reduced circult 6t? as heretofore described.

At the remote station R a control board St) is mounted upon a wall 12 and one section of this board includes an amber light 39' and a red light 31' which operate in unison with the lights 30 and 31 respectively. They may be properly identified by a tag 45. A suitable circuit 81 connects the amber light 36' in parallel with the light 30 and a circuit S2 connects the red light 31 in parallel with the red light 31 as indicated in broken lines at FIG. 9, or if desired, the lights may be arranged in series.

The arrangement illustrated at FIGS. 6 and 7 includes the box 32 at the extinguisher but is further modified in that it includes a signal box 33 at a remote station R which is formed with a speaker to emit an audible signal, a beeping sound, whenever the fire extinguisher is removed from its hook 13. Also, if desired, the date indicating box 46 and the lock box 5% may be located at this modified signal box 83 instead of at the housing box 32. Otherwise, the signalling apparatus at the box 32 is iden tical to that heretofore described. The extinguisher 11 is mounted upon a hangar 13 on a wall section 12 and a switch 2% is associated with the hangar 13. The housing box 32 includes an amber light 36 and a red light 31 operative as heretofore described. A power source 57 which is reduced in voltage by a transformer 59 which may be located in the wall 12 and the secondary lead 60 may extend to the box 32' as illustrated or the source 57, transformer 59 may be located at the wall 12' of the remote station R.

The audio signal box 83 at the remote station R, is mounted upon a wall 12. It is contemplated that this box will be substantially identical in form to the box 32 and will include prongs 38 to permit it to be plugged into a receptacle 34 in an outlet box 33' as in the manner heretofore described. The box will include a rear wall 37, side walls 4-1), a top 41 and bottom 42 the same as the box 32. However, the front wall 43' will be modified to include an enlarged opening 4 to receive a speaker $4. It will also include an amber light 30 which will operate in a flashing manner.

A modified arrangement of circuits will be required to obtain sufficient power to operate the speaker 8 1 and a suitable circuit arrangement is illustrated at FIG. 10. It is to be noted that this circuit includes all of the elements of the circuit heretofore described for the operation of the lights 35 and 31 in the box 32 and that the circuits to operate the speaker 84- and the light 3b in the speaker box 83 may be connected to the power leads 611a and 69b and to the leads controlling the relay 76. However, it is to be understood that certain of the leads heretofore described may be located at the box $3 instead of the box 32 as a matter of convenience and without altering the basic arrangement of the circuits.

The modified portion of the circuits of the box 83 are powered by continuations of the leads 611a and 60b extending from the transformer 59. These leads connect with a power supply loop 35, with the lead 60b connecting at a point in the loop between rectifiers 86 and as. The lead title is bifurcated with the legs 60a being connected into the loop 85 at the opposite sides of the rectifiers 86 and as, and with a capacitor 87 in each leg 6%. The loop is divided by a lead 88 having a capacitor 39 therein and a base voltage is established at the loop 85' between the rectifier as and the connection point 88' of the lead 88. This base voltage is established in a lead 9@ which extends to the several component circuits of the system. Selected voltage drops are established about the loop by resistors 91, 92 and 93 which are spaced between the connection point as and the rectifier 8d. Leads between these resistors extend from the loop 85 to the several component circuits of the system. These components include a pulsing means, a beeping means and a light-flashing means all as hereinafter described.

The pulsing means is powered by a lead 95' extending from the loop 85 between the resistors 91 and 92. The lead 95 is connected to extend through a first coil of a transformer 96, thence the collector and emitter of a transistor 97 and thence through the second coil of the transformer to a junction point 98. A lead 99 having a resistor 100 extends from the point 98 to the base lead 911 to establish a potential across the circuit. A second lead 101 having a resistor 102 and a capacitor 1% in series extends from the point 98 to the base of the transistor 97. A third lead 104 having a capacitor 15 extends from the point 98 to the base of a transistor 1116 which is in the circuit of the beeping means hereinafter described.

Operation of the pulsing means is initiated by oscillation between the transformer 96 and the transistor d7 due to a positive feed-back action. The oscillation permits a charge to be built up on the capacitor 103 which causes the base of the transistor 97 to become positive and cut off the flow through the transistor and thereby stop oscillations. The capacitor then discharges and in doing so creates a pulse at the junction 98. After discharging, oscillation will again commence until another charge is built up across the capacitor 103 and the cycle is repeated. These elements may be adjusted to pulse at any selected frequency, say, for example, 120 times per minute.

The beeping means is powered by a lead 1117 extending from the loop 85 between the resistors 92 and 93. The lead is connected to the primary of a transformer 103 to extend thence through the emitter and collector of the transistor 1%, thence through an RC filter 109 and to the base lead 99. A bias lead 111i is connected to the lead 104 with one portion extending to the lead 107 at a point adjacent to the loop and the other portion extending to the base lead 911. Suitable resistors 111 and 111 are positioned in this bias lead 116 at each side of the juncture point with the lead 104 to provide a proper voltage at the base of the transistor 1%.

The secondary of the transformer 108 is connected to the speaker 34- by a circuit loop 112 which includes a normally open switch 113 of a relay 114. This relay 114 is connected in parallel with the relay 76 and red light 31 as by a circuit loop 115. This relay 114 can thus be energized and close the switch 113 whenever the tire extinguisher 11 is lifted from the hook 13 to shift switch 219, to energize the circuits activating the relay '76 and lighting the red light 31, all as heretofore described.

it follows that operation of the beeping means is initiated by the pulsing action of junction 98 which changes the voltage at the base of the transistor 1% to permit a surge of current through lead 1117. This surge through the primary of transformer res initiates a like surge through the secondary of the transformer which, whenever the switch 113 is closed, will act upon the speaker 84 to produce an audible beep. Thus, through the relay 114, the action of the speaker is controlled directly by the operation of switch 211 when it is shifted to lead 26 by removing the fire extinguisher and subsequently by the holding relay '76.

The light flashing means is powered by a lead 116 extending from the loop 85 between the resistor X and the rectifier 86'. The lead is connected to the emitter and collector of a gating transistor 117 and thence to the light 311'. The base lead 9% is also connected to the light 313" to complete the circuit. A lead 118 extends from the base of the transistor 117 and to a bias lead 119 which is connected to the lead 107 at a point adjacent to the loop 85 and to the base lead hit. The bias lead includes a resistor 120 adjacent to the connection at base lead 919 and a transistor 121 adjacent to the connection at the lead 1M, and with the bias lead extending through the collector and emitter of the transistor 121. A lead 122 extends from the base of the transistor 121, to an RC filter 123 and to the lead 111? at a point adjacent to the emitter of the transistor 1% to complete the circuits.

It follows that operation of the light 311" is initiated from the lead 104 and pulsing action at the base of the transistor 1%, and which is amplified in lead 197. The effect of the pulse in lead 1%? is transmitted to the base of transistor 121 to permit a current surge through bias lead 119, which, in turn activates the lead 113 to energize the base of transistor 117. This effectively closes the circuit formed by lead 116 and base lead 9%. to flash the light Sit in synchronism with the pulsing generated at the pulser means. It is to be noted that this flashing will occur continuously but it may be adapted to occur only when the speaker 84 is not operating. Closing of the switch 113 to operate the speaker will change the current fiow through the lead 1137 and the filter 123 may be adjusted so that such a change will alter the voltage at the base of transistor 121 so that no current can flow through the lead 119 and with the effect that the flashing of the light 31?" will cease whenever switch 113 is closed to commence the beeping action of the speaker. However, it is to be noted that such arrangement is optional.

From the foregoing description of the components and their operation, it is apparent that a reliable, versatile system is possible to provide effective warning as to the use of fire extinguishers, and that with the components and circuits described, a simple, low cost operation is possible. However, it is further apparent that others skilled in the art can build and devise alternate and equivalent constructions which are nevertheless within the scope and spirit of my invention; hence, I desire that my protection be limited, not by the constructions illustrated and described, but only by the proper scope of the appended claims.

I claim:

1. In combination with a fire extinguisher and a hanger means for the same, a warning system adapted to indicate the presence, removal and return of a fire extinguisher on, from and to its hanger by emanation of selected, distinctive signals, and comprising: 1

(a) a two-way switch having a switch leg associated with the hanger means and being adapted to close with a first contact when the fire extinguisher is on the hanger and to close with a second contact when the fire extinguisher is removed from the hanger;

(b) a two-lead power supply, having a first lead connecting with said switch leg and having a second lead bifurcated to form two circuit loops with a first circuit being connected with said first contact and with a second circuit being connected with said second contact, whereby movement of the switch leg onto the first contact energizes the first circuit and movement of the switch leg onto the second contact energizes the second circuit;

() a pulsing means and a first light in said first circuit with the pulsing means being adapted to flash the light when the switch leg closes against said first contact to energize the said first circuit;

(d) a second light in said second circuit adapted to burn steadily when the switch leg closes against said second contact to energize the said second circuit;

(e) a holding lead shunting the switch leg and said second contact of the two-way switch;

(1) a normally open holding switch in the holding lead adapted to remain closed once it is closed; and,

(g) a closing means therefor in said second circuit to close the holding switch whenever the said second circuit is energized.

2. In the warning system set forth in claim 1, wherein the pulsing means in said first circuit includes a gating transistor in the circuit, a starting lead shunting the transistor having a capacitor therein and means extending from the starting lead, connecting with the base of the gating transistor adapted to effect flow and stoppage of flow of current through the transistor responsive to shifting current flow in the starting lead as the capacitor is charged and discharged.

3. In the warning system set forth in claim 1, wherein the pulsing means of the said first circuit includes a gating transistor, a gating circuit loop shunting said first light and connecting with the base and the emitter of the transistor, a starting transistor in the gating circuit loop, a starting lead shunting the gating transistor, a capacitor in this lead, and a bias lead extending from the starting lead to the base of the starting transistor, whereby the intermittent and charging and discharging of the capacitor in the starting lead creates varying potentials on the base of the starting transistor to permit an intermittent current flow therethrough and intermittent potential change on the base of the gating transistor to oscillate the current through the circuit suificient to flash said first light.

4. In the organization set forth in claim 1, including a remote lead in the first circuit and a remote lead in the second circuit and a light in each circuit adapted to operate in unison with the respective aforementioned first and second lights in the respective circuits.

5. In a warning system set forth in claim 1, including an extension of the power supply to a remote station, a circuit means in the extension at the remote station adapted to generate periodic impulses, a speaker connected with the impulse generating circuit means, a normally open relay switch in the circuit means, a circuit loop shunting the light of the said second circuit and a relay magnet in this loop adapted to close the normally open relay switch whenever the light in the said second circuit is burning and the relay magnet is also energized whereby and to efiect a periodic sound from the speaker,

responsive to the impulses of said impulse generating circuit means.

6. In the combination set forth in claim 1, wherein said closing means includes an energizing lead shunting the light in said second circuit, a relay coil in this lead, and a relay arm shiftable from a first position to a second position whenever the coil is energized, and wherein the aforesaid normally-open holding switch is mounted upon the relay arm to be open When the arm is at its first position, and to close whenever the arm shifts to its second position.

7. In the combination set forth in claim 6, including a normally-closed manually-operated switch, in the circuit including the energizing lead, adapted to be opened to de-energize the magnet coil of the relay and thereby permit the relay switch to open.

8. In combination with a fire extinguisher and a hanger means for the same, a warning system adapted to indicate the presence, removal and return of a fire extinguisher on, from and to its hanger by emanation of selected, distinctive signals, and comprising:

(a) a two-way switch at the hanger means having a switch leg and two opposing contacts with the leg being adapted to close upon a first contact when the fire extinguisher is on the hanger means and to close upon a second contact when the fire extinguisher is removed from the hanger means;

(11) a pair of electrical circuits having a common lead connecting with said switch leg and with the other lead of a first circuit connecting with said first contact and with the other lead of a second circuit connecting with said second contact, whereby movement of the switch leg onto said first contact closes the first circuit and movement of the switch leg onto said second contact closes the second circuit;

(0) a first signal means in the first said circuit adapted to emit a first signal whenever the circuit is closed as when the fire extinguisher is on the hanger means,

(0.) a second, distinctive signal means in the said second circuit adapted to emit a second signal whenever the second circuit is closed as when the fire extinguisher is removed from the hanger means;

(e) a holding lead in said second circuit connected in parallel with the leads extending to the switch leg and to said second contact;

(7) a normally open holding switch in this holding lead; and,

(g) means to close the holding switch in said second circuit when the said second circuit is closed by contacting the switch leg to said second contact and to continue to hold the holding switch closed after said switch leg is moved from said second contact, as by replacement of the fire extinguisher on the hanger, whereby said second signal means continues to emit its signal after the fire extinguisher is replaced, to thereby indicate that the fire extinguisher has been removed from and then replaced on the hanger.

9. In combination with a fire extinguisher and a hanger means for the same, a warning system adapted to indicate the presence, removal and return of a fire extinguisher on, from and to its hanger by emanation of selected, distinctive signals, and comprising:

(a) a two-way switch at the hanger means having a switch leg and two opposing contacts with the leg being adapted to close upon a first contact when the fire extinguisher is on the hanger means and to close upon a second contact when the fire extinguisher is removed from the hanger means;

(b) a pair of electrical circuits having a common lead connecting with said switch leg and with the other lead of a first circuit connecting with said first contact and with the other lead of a second circuit connecting with said second contact, whereby movement of the switch leg onto said first contact closes the 1 1 first circuit and movement of the switch eg onto said second contact closes the second circuit;

(c) a first signal means in the first said circuit adapted to emit a first signal Whenever the circuit is closed as when the fire extinguisher is on the han er means;

(0!) a second, distinctive signal means in the said second circuit adapted to emit a second signal whenever the second circuit is closed as when the fire eX tinguishcr is removed from the hanger means;

(a) a holding lead in parallel with the said second circuit;

(f) a normally open holding switch in this holding lead adapted to remain closed once it is closed;

(g) means in said second circuit to close said holding 12 switch when the circuit is energized by contacting said switch leg to said second contact; and, (11) signal means associated with the holding lead adapted to emit a signal when the said holding switch is closed.

References Cited in the file of this patent UNITED STATES PATENTS 1,758,546 Wartman May 13, 1930 1,885,309 1 Wagner Nov. 1, 1932 2,683,260 Lavclle July 6, 1954 2,694,803 Larson Nov. 16, 1954 2,754,498 Lavelle July 10, 1956 2,965,890 Robillard Dec. 20, 1960 

1. IN COMBINATION WITH A FIRE EXTINGUISHER AND A HANGER MEANS FOR THE SAME, A WARNING SYSTEM ADAPTED TO INDICATE THE PRESENCE, REMOVAL AND RETURN OF A FIRE EXTINGUISHER ON, FROM AND TO ITS HANGER BY EMANATION OF SELECTED, DISTINCTIVE SIGNALS, AND COMPRISING: (A) A TWO-WAY SWITCH HAVING A SWITCH LEG ASSOCIATED WITH THE HANGER MEANS AND BEING ADAPTED TO CLOSE WITH A FIRST CONTACT WHEN THE FIRE EXTINGUISHER IS ON THE HANGER AND TO CLOSE WITH A SECOND CONTACT WHEN THE FIRE EXTINGUISHER IS REMOVED FROM THE HANGER; (B) A TWO-LEAD POWER SUPPLY, HAVING A FIRST LEAD CONNECTING WITH SAID SWITCH LEG AND HAVING A SECOND LEAD BIFURCATED TO FORM TWO CIRCUIT LOOPS WITH A FIRST CIRCUIT BEING CONNECTED WITH SAID FIRST CONTACT AND WITH A SECOND CIRCUIT BEING CONNECTED WITH SAID SECOND CONTACT, WHEREBY MOVEMENT OF THE SWITCH LEG ONTO THE FIRST CONTACT ENERGIZES THE FIRST CIRCUIT AND MOVEMENT OF THE SWITCH LEG ONTO THE SECOND CONTACT ENERGIZES THE SECOND CIRCUIT; (C) A PULSING MEANS AND A FIRST LIGHT IN SAID FIRST CIRCUIT WITH THE PULSING MEANS BEING ADAPTED TO FLASH THE LIGHT WHEN THE SWITCH LEG CLOSES AGAINST SAID FIRST CONTACT TO ENERGIZE THE SAID FIRST CIRCUIT; (D) A SECOND LIGHT IN SAID SECOND CIRCUIT ADAPTED TO BURN STEADILY WHEN THE SWITCH LEG CLOSES AGAINST SAID SECOND CONTACT TO ENERGIZE THE SAID SECOND CIRCUIT; (E) A HOLDING LEAD SHUNTING THE SWITCH LEG AND SAID SECOND CONTACT OF THE TWO-WAY SWITCH; (F) A NORMALLY OPEN HOLDING SWITCH IN THE HOLDING LEAD ADAPTED TO REMAIN CLOSED ONCE IT IS CLOSED; AND, (G) A CLOSING MEANS THEREFOR IN SAID SECOND CIRCUIT TO CLOSE THE HOLDING SWITCH WHENEVER THE SAID SECOND CIRCUIT IS ENERGIZED. 